This invention relates to a device and system for carbureting liquid fuel for use in internal combustion engines and it particularly relates to such a device and system which ultrasonically vaporizes the liquid fuel, primarily for improving engine efficiency and reducing exhaust pollutants.
In the past few years, the conservation of petroleum type fuels has become a matter of deep worldwide concern, resulting in an international "energy crisis". It is well known that there is only a finite quantity of naturally occuring hydrocarbon fuels, including petroleum and natural gas available, as a natural resource, for energy use. Because of this "energy crisis" that has occured in the past few years, great efforts have been made to solve and/or alleviate the "energy crisis" Generally speaking, these efforts have been directed to two general areas of work. First, work is directed to developing new sources of energy. Secondly, much work is directed to conserving the available world supply of petroleum. The invention herein is primarily directed to alleviating the "energy crisis" by conserving petroleum energy and specifically by providing a more efficient use of the available energy, particularly liquid fuel, such as gasoline and the like. At the same time, the invention herein is directed to reducing air pollution caused by exhaust gases of internal combustion engines.
It is well known that higher fuel efficiencies in an internal combustion engine using liquid fuels, including gasoline, diesel fuel, jet fuel and the like, should be vaporized or gasified as completely as possible and mixed with the air in a finely divided state before ignition. Prior workers in the field have developed devices for generating vaporized fuel in a highly finely divided state by use of various devices, including devices which produce sound energy.
One device shown in the prior art which utilizes an ultrasonic device for vaporizing or atomizing a liquid fuel is shown in the Hundt U.S. Pat. No. 2,732,835. In this patent, the ultrasonically vaporized fuel is passed directly to a Venturi tube or, alternatively to a conventional carburetor. Other than the use of ultrasonic fuel gasification, the device appears to be conventional.
The Merritt U.S. Pat. No. 3,326,538 shows the use of a vapor generator, not using ultrasonics, for atomizing a fuel wherein the atomized fuel is throttled and the atomized fuel, after being mixed with air, is also throttled.
The Chapman U.S. Pat. No. 2,907,648 suggests that an ultrasonic device can be used in connection with carburetion of liquid fuels for internal combustion engines.
The Vang U.S. Pat. No. 2,414,494 shows a device for creating supersonic vibrations in a system for atomizing a liquid fuel. Ultrasonic energy does not appear to be used.
The Chertoff U.S. Pat. No. 2,745,372 shows a device which creates a siren effect for assisting in atomizing fuel in a basically conventional carburetor.
The Fruengel U.S. Pat. No. 2,908,443 shows the use of an ultrasonic carburetion device utilizing a transistor within an otherwise conventional carburetor of an internal combustion engine.
The Thatcher U.S. Pat. No. 3,533,606 shows an ultrasonic carburetion system wherein an ultrasonic device is located between the intake manifold and the fuel supply inlet. The fuel is drawn across the active surface of the device by negative pressure from the intake manifold of the engine. A fuel supply control mechanism is provided and uses a switching device as a fuel control unit for controlling the fuel supply volume passing to the sound wave producing device. It is believed that the device of the Thatcher patent is also the subject of an article entitled "Ultrasonic Fuel Systems," in the March, 1973 issue of Popular Science, pages 89, 90, 91 and 146.
The Ilford U.S. Pat. No. 3,613,649 shows the use of transducer energization being timed to selectively provide a solid atomized stream of fuel, as required, for use in fuel injection for an internal combustion engine.
The Sweeney U.S. Pat. No. 3,745,983 generally discusses the importance of atomization in achieving optimum air fuel ratios for combustion in an internal combustion engine.
The Hughes U.S. Pat. No. 3,780,945 shows a device which creates pressure waves wherein the device is used in an internal combustion engine to improve fuel atomization for cleaner burning of the fuel and better engine efficiency.
The Sata U.S. Pat. No. 3,860,173 shows the use of an ultrasonic fuel atomizer connecting the intake manifold of an internal combustion engine to a carburetor.
British Pat. No. 508,582 describes a carburetor system and method where atomization of the fuel is affected by the high frequency of vibrations of a member acting upon the fuel, wherein the vibratory action is restricted to the fuel and does not directly act on the combustion air which is mixed with the atomized fuel at a position removed from the surface of the fuel.
British Pat. No. 1,138,536 relates to the use of an ultrasonic device for atomizing fuels in an internal combustion engines.
It is apparent from the prior art that improved atomization of a fuel will provide for better engine efficiency, that is, the degree of combustion of the fuel, and it is also apparent from the prior art that various sound producing devices, including ultrasonic devices, can be used in a variety of ways to accomplish this purpose. However, the prior art devices, as shown in the above-identified patents, are deemed to be deficient in one or more respects. For example, in a number of the prior art devices, modifications of the intake manifold system are required. Prior art devices are also generally deficient in not disclosing a method by which engine demand is sensed for controlling the amount of energy necessary to generate the required fuel.
Also, it is considered a disadvantage that the gasified fuel requires a suitable nozzle arrangement for mixing the gasified fuel with air. Certain of the prior art devices suggests that additional devices, such as an air compressor or pumps are needed. Any such additional costs are, of course, highly disadvantageous.
From the foregoing, it is apparent that a carbureting device and system capable of improving engine efficiency and of reducing engine pollutants, which is simple in construction and which avoids many of the disadvantages of the prior art devices is a significant need in the art, particularly in view of the present concern for the preservation of available hydrocarbon fuels.